text: There are two modes for the operation of NSOM technique, with and without an aperture. These two mode have also been combined with the near-field Raman spectroscopy. The near-field aperture must be nanosized that complicates the probe manufacturing process. Also, the aperture method usually has a very weak signal due to weak excitation and Raman scattering signal. Overall, these factors lower the signal-to-noise ratio in aperature based NSOM/Raman technique. Apertureless probes are based on a metal-coated tip and provide a stronger signal.